    jQuery.extend({  
        createUploadIframe: function(id, uri)  
        {  
                //create frame  
                var frameId = 'jUploadFrame' + id;  
                  
                if(window.ActiveXObject) {  
                    var io = document.createElement('<iframe id="' + frameId + '" name="' + frameId + '" />');  
                    if(typeof uri== 'boolean'){  
                        io.src = 'javascript:false';  
                    }  
                    else if(typeof uri== 'string'){  
                        io.src = uri;  
                    }  
                }  
                else {  
                    var io = document.createElement('iframe');  
                    io.id = frameId;  
                    io.name = frameId;  
                }  
                io.style.position = 'absolute';  
                io.style.top = '-1000px';  
                io.style.left = '-1000px';  
      
                document.body.appendChild(io);  
      
                return io             
        },  
        createUploadForm: function(id, fileElementId, data)  
        {  
            //create form     
            var formId = 'jUploadForm' + id;  
            var fileId = 'jUploadFile' + id;  
            var form = $('<form  action="" method="POST" name="' + formId + '" id="' + formId + '" enctype="multipart/form-data"></form>');   
            var oldElement = $('#' + fileElementId);  
            var newElement = $(oldElement).clone();  
            $(oldElement).attr('id', fileId);  
            $(oldElement).before(newElement);  
            $(oldElement).appendTo(form);  
              
            //增加文本参数的支持  
            if (data) {  
                for (var i in data) {  
                    $('<input type="hidden" name="' + i + '" value="' + data[i] + '" />').appendTo(form);  
                }  
            }  
              
            //set attributes  
            $(form).css('position', 'absolute');  
            $(form).css('top', '-1200px');  
            $(form).css('left', '-1200px');  
            $(form).appendTo('body');         
            return form;  
        },  
      
        ajaxFileUpload: function(s) {  
            // TODO introduce global settings, allowing the client to modify them for all requests, not only timeout          
            s = jQuery.extend({}, jQuery.ajaxSettings, s);  
            var id = new Date().getTime()          
            var form = jQuery.createUploadForm(id, s.fileElementId, s.data);  
            var io = jQuery.createUploadIframe(id, s.secureuri);  
            var frameId = 'jUploadFrame' + id;  
            var formId = 'jUploadForm' + id;          
            // Watch for a new set of requests  
            if ( s.global && ! jQuery.active++ )  
            {  
                jQuery.event.trigger( "ajaxStart" );  
            }              
            var requestDone = false;  
            // Create the request object  
            var xml = {}     
            if ( s.global )  
                jQuery.event.trigger("ajaxSend", [xml, s]);  
            // Wait for a response to come back  
            var uploadCallback = function(isTimeout)  
            {             
                var io = document.getElementById(frameId);  
                try   
                {                 
                    if(io.contentWindow)  
                    {  
                         xml.responseText = io.contentWindow.document.body?io.contentWindow.document.body.innerHTML:null;  
                         xml.responseXML = io.contentWindow.document.XMLDocument?io.contentWindow.document.XMLDocument:io.contentWindow.document;  
                           
                    }else if(io.contentDocument)  
                    {  
                         xml.responseText = io.contentDocument.document.body?io.contentDocument.document.body.innerHTML:null;  
                        xml.responseXML = io.contentDocument.document.XMLDocument?io.contentDocument.document.XMLDocument:io.contentDocument.document;  
                    }                         
                }catch(e)  
                {  
                    jQuery.handleError(s, xml, null, e);  
                }  
                if ( xml || isTimeout == "timeout")   
                {                 
                    requestDone = true;  
                    var status;  
                    try {  
                        status = isTimeout != "timeout" ? "success" : "error";  
                        // Make sure that the request was successful or notmodified  
                        if ( status != "error" )  
                        {  
                            // process the data (runs the xml through httpData regardless of callback)  
                            var data = jQuery.uploadHttpData( xml, s.dataType );      
                            // If a local callback was specified, fire it and pass it the data  
                            if ( s.success )  
                                s.success( data, status );  
          
                            // Fire the global callback  
                            if( s.global )  
                                jQuery.event.trigger( "ajaxSuccess", [xml, s] );  
                        } else  
                            jQuery.handleError(s, xml, status);  
                    } catch(e)   
                    {  
                        status = "error";  
                        jQuery.handleError(s, xml, status, e);  
                    }  
      
                    // The request was completed  
                    if( s.global )  
                        jQuery.event.trigger( "ajaxComplete", [xml, s] );  
      
                    // Handle the global AJAX counter  
                    if ( s.global && ! --jQuery.active )  
                        jQuery.event.trigger( "ajaxStop" );  
      
                    // Process result  
                    if ( s.complete )  
                        s.complete(xml, status);  
      
                    jQuery(io).unbind()  
      
                    setTimeout(function()  
                                        {   try   
                                            {  
                                                $(io).remove();  
                                                $(form).remove();     
                                                  
                                            } catch(e)   
                                            {  
                                                jQuery.handleError(s, xml, null, e);  
                                            }                                     
      
                                        }, 100)  
      
                    xml = null  
      
                }  
            }  
            // Timeout checker  
            if ( s.timeout > 0 )   
            {  
                setTimeout(function(){  
                    // Check to see if the request is still happening  
                    if( !requestDone ) uploadCallback( "timeout" );  
                }, s.timeout);  
            }  
            try   
            {  
               // var io = $('#' + frameId);  
                var form = $('#' + formId);  
                $(form).attr('action', s.url);  
                $(form).attr('method', 'POST');  
                $(form).attr('target', frameId);  
                if(form.encoding)  
                {  
                    form.encoding = 'multipart/form-data';                
                }  
                else  
                {                 
                    form.enctype = 'multipart/form-data';  
                }             
                $(form).submit();  
      
            } catch(e)   
            {             
                jQuery.handleError(s, xml, null, e);  
            }  
            if(window.attachEvent){  
                document.getElementById(frameId).attachEvent('onload', uploadCallback);  
            }  
            else{  
                document.getElementById(frameId).addEventListener('load', uploadCallback, false);  
            }         
            return {abort: function () {}};   
      
        },  
      
        uploadHttpData: function( r, type ) {  
            var data = !type;  
            data = type == "xml" || data ? r.responseXML : r.responseText;  
            // If the type is "script", eval it in global context  
            if ( type == "script" )  
                jQuery.globalEval( data );  
            // Get the JavaScript object, if JSON is used.  
            if ( type == "json" )  
            	data = r.responseText; 
	            var start = data.indexOf(">"); 
	            if(start != -1) { 
	               var end = data.indexOf("<", start + 1); 
	               if(end != -1) { 
	                   data = data.substring(start + 1, end); 
	              } 
                }
                eval( "data = " + data );  
            // evaluate scripts within html  
            if ( type == "html" )  
                jQuery("<div>").html(data).evalScripts();  
                //alert($('param', data).each(function(){alert($(this).attr('value'));}));  
            return data;  
        },
        
        //因为Jquery版本问题   补充的方法 不然会报错
        handleError: function( s, xhr, status, e )      {  
            // If a local callback was specified, fire it  
                    if ( s.error ) {  
                        s.error.call( s.context || s, xhr, status, e );  
                    }  
      
                    // Fire the global callback  
                    if ( s.global ) {  
                        (s.context ? jQuery(s.context) : jQuery.event).trigger( "ajaxError", [xhr, s, e] );  
                    }  
        } 
    })  